A New Zealander who managed North Korea’s first budget travel agency, Young Pioneer Tours (YPT), has died, according to reports. YPT said in a statement that Troy Collings, 33, died last week of a heart attack.

“Troy was instrumental in establishing Young Pioneer Tours as one of the leading travel companies for North Korea. We here at YPT have lost a visionary and a true pioneer to the travelling industry,” it reads on YPT’s website.

Collings co-founded YPT in 2008 with friend Gareth Johnson. Collings believed that bringing tourism to North Korea could positively influence the country’s development and help the people there.

"The hurdles were less than most people would expect, but that was mostly due to good relations, with good partners we had formed in Pyongyang over our visits," Collings said about establishing the travel agency in the world’s most isolated nation.

Travelers on YPT tours see North Korea’s capital, Pyongyang, along with more rural parts of the country. YPT is based in China, and seeks to “push the envelope for opening tourism in places often forgotten.” The company also reportedly offers "secret tours" to Syria and Afghanistan.

The tour company gained notoriety after it was found that American college student Otto Warmbier had used the agency to book his trip to North Korea.

Warmbier was detained by North Korea before he could leave the country on Jan. 2, 2016, after North Korea claimed he stole a flag from his hotel. After 17 months in captivity, he was returned to the U.S. in June 2017 in a coma and died six days later.

Since Warmbier’s death, YPT decided to no longer take U.S. citizens into North Korea. Since September 2017, the U.S. government has also forbidden Americans from traveling to North Korea, due to reports of North Korean authorities detaining Americans without charges.

Only 4,000 to 6,000 western tourists visit North Korea each year. The country has recently built several ski and spa resorts intended to attract Chinese visitors.